Numbers as Adjectives

A subscriber recently wrote in with a question that’s a good followup to last week’s Tip of the Week, Writing Numbers:
“When are hyphens used with numbers? Is it 13 feet or 13-feet; 12 hours or 12-hours?”

Rule: Generally, hyphenate between two or more adjectives when they come before a noun and act as a single idea.

This rule can also be applied when a number and a measurement unit taken together form an adjective, that is, when they describe another object.

Examples:
A 22-inch monitor is too big for my desk.
Nurses work 12-hour shifts.
Anthony swung his five-pound hammer.
In the previous sentences, the measurements, such as 22-inch, describe specific objects, such as monitor.

When measurements are not acting as adjectives, hyphens are not needed.

Examples:
Suzanne won the race by 25 yards.Twelve hours later, she was exhausted.
Anthony’s hammer weighs five pounds.

Pop Quiz: Choose A or B.

1. A. I can’t believe she wrote a 33-page treatise on how to screw in a light bulb.
1. B. I can’t believe she wrote a 33 page treatise on how to screw in a light bulb.

2. A. I can’t believe she wrote 33-pages on how to screw in a light bulb.
2. B. I can’t believe she wrote 33 pages on how to screw in a light bulb.

3. A. Harold found a 110-year-old book at the flea market.
3. B. Harold found a 110 year old book at the flea market.

4. A. Harold found a book that must have been 110-years-old at the flea market.
4. B. Harold found a book that must have been 110 years old at the flea market.

Answers

1. A.
2. B.
3. A.
4. B.

Posted on Thursday, March 5, 2009, at 4:07 pm

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As we replied to Devon on November 23, 2011, that is only correct if the letter I is italicized in the sentence. Individual letters and combinations of letters of the Latin alphabet are usually italicized.

I is the ninth letter in the alphabet.I is a letter followed by J.I is the first letter in the word instant.

Your sentence is grammatically correct; however, it may sound awkward to some people due to the omission of the understood word am: “The fact that she is taller than I am is not that important–unless you are buying us clothing!”

There are several instances where you can say “I is,” and I am not talking about Ebonics. Are you ready? Here we go; I is a proper noun. I is the ninth letter in the alphabet. I is a vowel. I is the first letter in the word impressive.

You are correct; however, Chicago Manual of Style’s Rule (7.58) states, “When a word or term is not used functionally but is referred to as the word or term itself, it is either italicized or enclosed in quotation marks.”
For instance:I is a proper noun. OR “I” is a proper noun.

You tell ’em, GrammarBook! (How dare he try to tell YOU how to use quotation marks! And being wrong, in the process!) I love you guys, and thank God for Jane Straus! (Also: Should I have used that comma before “in the process”?) Thank you for fighting to defend our precious rules.

My daughter’s school has this practice of asking the pupils to clap their hands once and then keep quiet. Some teachers do it by saying “Give me a silent clap.” while others say “Give me a silence clap.” Should it be a ‘silence clap’ or a ‘silent clap’? How do I explain to my daughter?

Actually, neither expression makes much sense and would be called an oxymoron. But if you have to choose, then “silent clap” because “silent” is an adjective describing “clap” while “silence” is a noun.

Deciding whether to use a or an before abbreviations can be tricky. The abbreviation for Frequently Asked Questions (FAQ) causes confusion because it can be pronounced as a word (fak), or one letter at a time (F-A-Q). Using the guidelines above, one would say a FAQ when it is pronounced as one word, and an FAQ when it is pronounced one letter at a time.

Your first two are similar to our examples in the blog “Numbers as Adjectives” and the last, if used with a noun such as twin-engine aircraft, is an example of a compound adjective. These are all grammatically correct. Twin-engine aircraft are still common. We’re not experts on guns, but two-barreled guns were probably more common in the past. “One-legged man” has become a less common expression as medical science has become more adept at fitting people who have lost all or part of a leg with a prosthesis.

According to the Cambridge Dictionary, dozen is a countable noun, not plural (collective). According to WikiAsk, dozen is not a collective noun. So probably you’re wrong, unless you can cite where you find it as a collective noun?

Hi! I am confused. Are numbers adjectives or determiners? How to differentiate them?
E.g. I’m going to ask you three questions.
The camel has two humps.
Which one is adjective? Which one is determiner? Or is it the both of them are of the same word class?

Determiners are words placed in front of a noun to introduce and contextualize a noun, often in terms of quantity and possession. Determiners include articles (a, an, the), demonstratives (this, that, these, those), possessives (my, your, our, etc.), and quantifiers (some, few, many, and cardinal numbers). Determiners are always placed in front of a noun. The numbers in your sentences are quantifiers.

Until recently, traditional grammar and many dictionaries did not take determiners into account. Many determiners were classed as adjectives. Today many grammarians prefer to distinguish determiners as a separate class from adjectives.

Hi, I have a question regarding numbered adjectives. I commonly see nine-tailed with ed but also sometimes nine-tail without ed. Also multi-colored vs. multi-color. Is it safe to assume ed isn’t needed if there’s a measurement associated with the modifier?

The phrase nine-tailed is a compound adjective, as in “nine-tailed fox.” We have not seen it written “nine-tail.”

We are not able to find any authoritative rule regarding the use of -ed with a modifier, although most compound adjectives, like your example above, use -ed. Many writers now use -size instead of -sized, as in a bite-size morsel or a king-size pillow.

The words multicolored and multicolor do not have hyphens. Most dictionaries, including the American Heritage Dictionary and the Oxford Advanced Learner’s Dictionary, identify both words as adjectives with the exact same meaning and appear to use them interchangeably.

Not all authorities agree in the area of spelling out numbers versus using numerals. The AP Stylebook, for instance, recommends spelling out only the numbers one through nine. We recommend writing decimals using figures, but the New Yorker would say “one and a half” or “one point five.” It’s the writer’s call here.

A quantity of weight or measure is singular when considered as a unit. Also, our Rule 1 of Writing Numbers says, “Spell out all numbers beginning a sentence.” Although an argument can be made for “Two meters of fabric is here” and “There is three kilograms of flour in the kitchen,” to native speakers of English those sentences sound awkward. We suggest rewriting these sentences. For example, “I have two meters of fabric here” and “I have three kilograms of flour in the kitchen.”

I think there is a problem with the example in rule 8 of the hyphen section.
This is what it states:

Rule 8. Hyphenate all spelled-out fractions.

Example: more than two-thirds of registered voters

In the example, two-thirds is not acting as an adjective; instead, it is a noun. Therefore, “two-thirds” must not be hyphenated. It should only be hyphenated in cases where it is an adjective, such as: “a two-thirds cup of flour.”

Our rules, guidance, and examples are based on areas of general agreement among the authorities. We tend to favor The Chicago Manual of Style and The Associated Press Stylebook. These highly regarded reference books agree on hyphenating fractions in noun, adjective, and adverb forms.

Hello, my question is about when to use a noun preceded by a numerical in possessive form and when as a part of a single unit as an adjective: e.g. two days’ leave and a two-day holiday? Thank you in advance.

Could I simply use the hyphens throughout (i.e., between the numbers and in the compound modifiers) in the following constructions in lieu of suspended hyphenation? Unfortunately, I cannot recast these examples. Oftentimes, the hyphen can be used as the word “to” in this manner.

Regarding your first question, yes to the part about to. There may be rare exceptions, but this is a valuable rule of thumb. With and or or, it depends. Sometimes a suspensive hyphen is needed, but not always. Use it if the sentence is differentiating discrete elements.

All your other examples are correct. The repeat of the percentage sign in the third example is recommended, as are the two dollar signs in the last example.

Suspensive hyphenation is not used with to because to usually signals a range, which logic suggests should not be broken up with a space.

Regarding your first two examples, these are the writer’s call. There are no set rules. Different editors have different approaches. We would probably use commas, or rewrite.

Again, the writer’s call as there are simply no definitive policies we could find. Our thinking is that while you might say “this is a five-foot-ten woman,” you would not say “this is an eleven-pound-eight baby.” Therefore, we’d go with a comma for weight: an eleven-pound, eight-ounce baby but a hyphen for height: a five-foot-ten-inch woman.

Your first example does not require hyphens. Our post Hyphens with Numbers says, “When numbers are not used as compound adjectives preceding nouns, don’t use a hyphen.” Also, our Rule 8a of Writing Numbers says, “When writing out a number of three or more digits, the word and is not necessary.” However, “digital camera” could be viewed as a compound adjective. Therefore, the sentence should be written It contained three hundred sixty individual digital-camera chips. Your second example contains two compound adjectives. He bought two 1/4-scale-sized radio-controlled cars.

Hello! I would like to know the usage of the indefinite article in phrases like “an amazing two days” and “an awful two days”. Is is just following the “a/an + adjective + number + plural noun” formula or is there a grammar rule for it? Also, why do we have to say “let go of my arm” (with the preposition “of”) and not “let go of me” (“as opposed to let me go”)? Thanks in advance

The indefinite article an was used in your first example phrases since you are referring to a nonspecific noun (“days”), and the first letter of the word following the article has the sound of a vowel. Coincidentally, our weekly e-newsletter article of March 22, 2017, which will be posted on our blog tomorrow, discusses a, an, and the in detail.

The sentences “Let go of my arm,” “Let go of me,” and “Let me go,” are all grammatically correct.

Hello,
I am writing a report talking about a setup in a experiment. Which following form I should rather use and if “block” should be plural?
4-block configuration
Four block configuration
Four-block configuration

To be fair, conventions for single vs. double quotation marks differ widely, especially when considering Canadian, British, and American English. American English tends to default to the double quotes except where using a second-level quotation inside another. British English has the opposite convention, but is more likely to distinguish between speech and other usages by varying the type of quotation marks used. Canadian English uses double quotes for speech, but tends to use single quotes to demarcate most anything else.

Illnesses have a time of evolution called progress. In med reports, this is usually found with a number of days the person has presented the illness. I dont know if I should say “two-day progress,” “two-days progress,” “two-days’ progress,” or something else. Written differently, I could say “The progress has been going on for two days,” but it’s too long and we appreciate brevity. Can you advise?

In the sentence, “there is no difference between the two,” Is “two” still considered an adjective? Or is it now a noun since it is replacing whatever 2 things you’re determining the difference between?

In this case two is the object of a prepositional phrase in which the potentially understood noun that two would modify is omitted. Therefore, it is a noun in your sentence (consistent with its noun definition: https://www.dictionary.com/browse/two).

The compound adjectives 24-hour and eight-hour modify the singular nouns service and workday; therefore, the word hour is singular.
Another way to look at it is that the singular is used to describe and the plural to count.
Examples:We offer 24-hour service.
We offer service 24 hours a day.

Thank you for your explanation. After years seeing English speakers misusing the apostrophe in this way (adjective vs. possessive), I really needed confirmation.
On a related topic, whenever the noun is used as an adjective, should we not refrain from using plural (as it is with adjectives in English), e.g. “The answer came with a 4 day delay”? Thank you.

Our post Hyphens with Numbers offers a more thorough explanation. When you are combining two or more words to form a compound adjective in front of a noun, put hyphens between these words (a 33-page book). When numbers are not used as compound adjectives preceding nouns, don’t use a hyphen (the book contains only 33 pages). We suggest you read this post along with the quiz and comments that follow.

My linguistics professor told me that in phrases like “two-floor building” or “eight-page book,” “two-floor” and “eight-page” are nouns simply acting like adjectives, because the final word in the compound is a noun and English is a right-headed language. Now, the logic of this makes sense in a way because the other compound words worked well like this, such as “scarecrow” or “runway,” the second word determining the part of speech. However, I simply can’t wrap my head around the idea that “eight-page” is a noun because no one would ever use it as a noun. Can’t it just be an adjective, an exception to the right-headed rule?

As we are not linguists, we will have to respond as grammarians. To us, two or more words that come before the noun they modify and act as a single idea are called compound adjectives, and they are generally hyphenated (see our Rule 1 of Hyphens Between Words). Therefore, for grammarians, two-floor and eight-page in your examples are compound adjectives. These are different from standard compound words such as scarecrow and runway. Your professor probably meant “right-headed” to be more of a guideline than a rule. Consider the word runaway. It is a compound noun meaning “a person who has run away.” It is rare that the word away is used as a noun; it is most frequently an adverb and sometimes an adjective.

If I am referencing more than one century in a sentence, would I use a hyphen? For instance: She is a gallery owner specializing in late 19th and early 20th century decorative arts. And are those two references to the century considered compound adjectives? Thank you!

According to the Chicago Manual of Style’s section 7.87: Multiple hyphens, “Multiple hyphens are usually appropriate for such phrases as an over-the-counter drug or a winner-take-all contest. If, however, the compound modifier consists of an adjective that itself modifies a compound, additional hyphens may not be necessary. The expressions late nineteenth-century literature and early twentieth-century growth are clear without a second hyphen.”

Therefore, we recommend “She is a gallery owner specializing in late nineteenth- and early twentieth-century decorative arts.”
However, if you were to follow the AP (Associated Press) Stylebook, you would write “She is a gallery owner specializing in late 19th and early 20th century decorative arts.”
Either method would be acceptable, just be consistent.

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